Harmonograph



United States Patent Office 3,496,641 Patented Feb. 24, 1970 3,496,641 HARMONOGRAPH Glen W. Mills, Newberg, reg., assiguor of fifty percent to Willard L. Kenuon, Astoria, Oreg. Filed Aug. 12, 1968, Ser. No. 752,007 Int. Cl. B431 11/02 US. CI. 3327 4 Claims ABSTRACT OF THE DISCLOSURE A harmonograph including pendulums mounted for universal swinging movement which support a recording instrument such as a piece of paper and a writing instrument. The mounting for each pendulum comprises vertically spaced support members, each mounted through a pair of pins for pivoting about a horizontal axis. The pivot axis for one member extends transversely of the pivot axis for the other member and the pendulum extends downwardly through an opening in one of the support members to a weighted bottom.

This invention relates generally to harmonographs, and more particularly to improvements in the mounting of one or more pendulums which ordinarily are present in a harmonograph.

The harmonograph contemplated by a preferred embodiment of the invention includes a pair of laterally spaced pendulums, each of which is suspended from a mounting accommodating swinging of the pendulum in any direction, either in a single vertical plane or with the pendulum also partaking of movement out of such a plane. A general object of the invention is to provide a unique harmonograph featuring novel means for supporting a pendulum which affords such movement.

Harmonographs, by reason of their including pendulums and generally requiring structure for supporting such pendulums, tend by their nature to be rather massive in construction. Thus, for practical reasons, it is preferable that they be dismantleable to permit their being set up at different locations. Another object of the invention, therefore, is to provide a unique form of harmonograph which fulfills these requirements.

Preferably, and as contemplated by this invention, the structure which dependently supports a pendulum for universal swinging movement also may form part of the detachable structure serving to hold detachable frame sections in the harmonograph together.

A particular feature and object of the invention is the provision of novel means for dependently supporting a pendulum, permitting the pendulum to swing in any direction, comprising a pair of supports stacked one over the other, each of which is pivotable about a horizontal axis with the pivot axes for the two supports extending normal to each other. The pivot mounting for a support comprises spaced pins upon which the support rests, the pins being located on diametrically opposite sides of the pendulum which extends downwardly through one of the supports.

A further and more specific object of the invention is the provision of a novel socket and groove on the underside of a support for receiving the pins which the support rests upon. The organization eliminates the need for close tolerances in making a pendulum mounting which will swing freely. Further, misalignment which might occur as a result of mishandling or rough usage does not seriously impair the operability of the mounting.

Another object is to provide a novel construction for a universal type mounting suitable for use such as supporting a pendulum or similar device.

These and other objects of the invention will become more fully apparent as the following description is read in conjunction with the accompanying drawings, wherein:

FIG. 1 is a perspective view of a harmonograph having pendulums depending from universal mountings;

FIG. 2 is a side elevation view, reduced in scale, of the harmonograph shown in FIG. 1;

FIG. 3 is a side elevation view, somewhat enlarged, of a universal mounting in the harmonograph, the view being taken generally along the line 33 in FIG. 1; and

FIG. 4 is an exploded perspective view of the universal joint in FIG. 3.

Referring now to the drawings, and first more specifically to FIGS. 1 and 2, at 10 is indicated generally a harmonograph. The harmonograph is an apparatus which is adapted to illustrate graphically the integration of two oscillating motions moving at an angle to each other, as will be more fully described below. In the harmonograph illustrated, the two oscillating motions involved are those produced by a pair of pendulums, shown at 8 and 9.

The harmonograph further includes an upright frame, indicated generally at 12, supporting the pendulums. The frame comprises a pair of inverted, U-shaped, laterally spaced apart bars 16, 18. Bars 16, 18 have top expanses 16a, 18a which are relatively closely spaced together. Legs 16b, 18b in the bars flare outwardly progressing downwardly to provide a stable wide base for the harmonograph.

A pair of annular plates 19 extend across the tops of expanses 16a, 18a, and these are secured by bolts 21 and nuts 23 to these expanses, thus to interconnect the upper parts of the frame bars. A pair of spaced apart end braces, 20, 22 are secured, as by detachable fasteners 25 to opposed legs 16b, 18b in the frame. laterally spaced parallel side braces 24, 26 extend longitudinally of the frame, and are secured adjacent opposite sets of their ends of end braces 20, 22 by similar detachable fasteners.

A shallow pan 30 adapted to hold drawing supplies spans the region between side braces 24, 26. This may be detachably secured along its edges to the side braces, to lend additional rigidity to the frame.

Pendulums 8 and 9 are similar in construction. With reference to pendulum 8, it will be noted that each comprises an elongated upright tube or shaft 40, at the bottom of which is secured a hollow cannister 42. The cannister has a capped opening 44 extending through its top, permitting it to be filled with water, sand, or other material to weight the lower end of the pendulum. Shaft 40 extends upwardly from cannister 42 through the center of one of the plates 19 securing the frame bars together.

The upper end of each pendulum is dependently supported from frame 12 through a universal mounting, such as the mounting shown at 48. These universal mountings will now be described in detail.

Referring now also to FIGS. 3 and 4, each universal mounting comprises a pair of supports stacked one over the other such as those shown at 56, 58 for mounting 48. The lower support is annular and encircles pendulum shaft 40 which extends through the center thereof. The upper support spans the annular support and has the upper end of pendulum shaft 40 secured thereto adjacent its center.

Lower support 56 is pivotally supported over the top of annular plate 19 though resting it on the pointed or reduced ends 60 of bolts 21 used in securing plate 19 to the frame bar. These bolts, therefore, constitute pins on diametrically opposite sides of the pendulum shaft providing for pivotal movement in the support 56. A dimple or socket 62 indented inwardly from the under surface of support 56 receives the pointed end of one of the bolts 21. An elongated groove 64 indented inwardly from the under surface of support 56, on the diametrically opposite side of the support receives the pointed end of the other of bolts 21. The socket and groove serve to retain the annular support approximately centered over annular plate 19 with both functioning to inhibit displacement in a direction normal to the pivot axis afforded by the pointed ends of the bolts and the socket inhibiting displacement in a direction paralleling the pivot axis. The construction in one, however, which does not require an exact spacing between the pointed ends of the bolts to permit the same to be operatively received under the support in a position alfording free pivotal movement. W

The mounting of support 58 above support 56 is somewhat similar to the construction just described. Thus, and more specifically, joined to and projecting downwardly mm the underside of support 58 are a pair of pins 70 on diametrically opposite sides of the pendulum shaft. These have reduced, or pointed, ends at their lower extremities which are received within a socket, or dimple, 72 provided on the top of support 56 on one side of the support, and a groove 74 provided on the top of support 58 on the diametrically opposite side of the support. The pointed ends of pins 70 provide a generally horizontal pivot axis for support 53 which extends normal to the pivot axis provided by the pointed ends of bolts 21.

It will be noted, and with reference to FIG. 3, that the pointed ends of the pins projecting downwardly from support 58 are in substantially the same plane as the pointed ends of the pins projecting upwardly toward the underside of support 56. This is effective to place the two pivot axes provided by the two sets of pins in substantially the same plane.

A table is shown at 86 which is detachably secured to the pendulum shaft of one pendulum by means of a bracket 82 and detachable fasteners 83. The table, which may take the form of a clipboard, is included to provide a support for a piece of paper or other form of recording material.

The other pendulum mounts an arm 90 which is journaled for up and down swinging movement about a horizontal axis at 93 on a bar 95. The bar is joined to a bracket 97 and the latter is secured through detachable fasteners to the pendulum shaft of this other pendulum. The remote, or free, end of arm 90 includes means 96 by which a writing instrument such as a pen or pencil 94 may be secured in a fixed position on this remote end. It will be noted that arm 90 includes a looped portion which partially extends about the pendulum shaft of the other pendulum. This may function as a counterweight for holding the arm upright when the same is lifted upwardly, as for the purpose of replacing the paper held en table 86.

Operation of the harmonograph is initiated by starting swinging movement of one of the pendulums in one vertical plane and swinging movement of the other pendulum in another vertical plane. With the writing instrument resting on the paper carried by table 86, the motions of the two pendulums will be integrated and a graphic illustration of such integrated motion will be produced on the paper.

The harmonograph described is readily broken down to permit its movement from one place to another. When setting up the harmonograph, the annular plates 19 together with the side and end braces described serve rigidly to hold the two frame bars in proper spaced apart position. The two universal mountings provided in the device for the pendulums are easily assembled with the Weight of a pendullm serving to hold the parts in its associated mounting together.

Relatively friction free swinging of each pendulum on the two supports in its associated mounting is provided by the pairs of pins which the supports rest upon. No close tolerances must be adhered to in the placement of the pins. With the type of swinging movement provided for any given pendulum being the combined result of two pivot mountings affording pivotal movement about axes disposed normal to each other, random swinging movement is afforded a pendulum in any or multiple vertical planes and in a path which moves out of a vertical plane. The universal mounting described is particularly useful in applications such as the harmonograph herein illustrated where it is desired to provide random swinging movement in a device, such as the penduluins shown, simply and without the necessity of precisely aligned components.

While a particular embodiment of the invention has been described, it'should be obvious that modifications and variations are possible without departing therefrom.

It is claimed and desired to secure by Letters Patent:

1. In a harmopograph including a frame and a pendulum,

first and second pendulum supports, pivot means comprising a first pair of upright pins disposed on diametrically opposite sides of said pendulum interposed between the first support and said frame, said first pair of pins having reduced ends disposed in a horizontal plane and providing a first pivot axis for the first support which extends through the ends of the pins, pivot means comprising a second pair of upright pins disposed on diametrically opposite sides of said pendulum interposed between said first support and the second support, said second pair of pins having reduced ends disposed in a horizontal plane and providing a second pivot axis for the second support which extends through the ends of said second pair of pins, said second pivot axis provided for the second support by the second pair of pins being disposed at an angle to said first pivot axis, one of the reduced ends of a pair of pins being received within a recessed socket and the other of the reduced ends of said pair of pins being received within an elongated groove aligned with the socket, and

means depending the pendulum from said second support.

2. The harmonograph of claim 1, wherein the reduced ends of said first pair of pins project upwardly from said frame and support a bottom side of said first support, the reduced ends of the second pair of pins project downwardly from said second support and rest on a top side of said first support, and said top and bottom sides of said first support are so shaped that the reduced ends of the first and second pairs of pins are in a substantially common plane.

3. The harmonograph of claim 1, wherein the reduced ends of the first pair of pins project upwardly from said frame and support a bottom side of said first support, said socket and groove are defined in the bottom side of said first support and receive the reduced ends of said first pair of pins, the reduced ends of said second pair of pins project downwardly from said second support and rest on a top side of said first support, another recessed socket is defined in the top side of said first support receiving the reduced end of one of the pins in said second pair, and another elongated groove aligned with said other socket is defined in the top side of said first support receiving the reduced end of the other of the pins in said second pair.

4. A universal mounting for supporting a device on a frame and permitting random swinging of the device relative to the frame comprising first and second supports,

pivot means comprising a first pair of spaced apart upright pins interposed between the first support and the frame, the pins in said first pair having reduced ends disposed in a substantially horizontal plane and providing a first pivot axis for the first support which extends through the ends of the pins, and

5 6 pivot means comprising a second pair of spaced apart within a recessed socket and the other of the reduced upright pins interposed between said first support and ends of said pair of pins being received within an the second support, the pins in said second pair elongated groove aligned with the socket.

having reduced ends disposed in a substantially horizontal plane and providing a second pivot axis for the second support which extends through the References Cited UNITED STATES PATENTS reduced ends of the pins in said second pair, said 898 599 9/1908 ce second pivot axis provided for the second support 3 36092O 1/1968 Heim 58 129 X by the Second P Of pins being disposed at a 3384966 5/1968 Lias.

angle to said first pivot axis, 1

O a one of the reduced ends of a pair of pins being received HARRY N. HAROIAN, Primary Examiner 

